Tourists walk past as U.S. Park Service workers remove barricades that were used to close the Martin Luther King Memorial on the morning after a bipartisan bill was passed by the House and the Senate to reopen the government and raise the debt limit, Oct. 17, 2013.

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A U.S. Park Service employee cleans the windows inside the information center at the Martin Luther King Memorial on the morning after a bipartisan bill was passed by the House and the Senate to reopen the government and raise the debt limit, Oct. 17, 2013.

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U.S. Capitol tour guide Katherine Minahan conducts a tour in Statuary Hall of the U.S. Capitol upon returning to work, Oct. 17, 2013.

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A dog pulls its owner past the Martin Luther King Memorial which is filled with tourists one day after a bipartisan bill was passed by the House and the Senate to reopen the government, Oct. 17, 2013.

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Eighth graders from Normandy High School in Parma, Ohio pose for a picture at the "Bread Line" statue at the FDR Memorial in Washington, Oct. 17, 2013.

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Richard Doerner, a museum specialist at the U.S. Capitol who returned to work today after being furloughed for the past two weeks, listens for sounds of ticking after winding the Ohio Clock outside the Senate chamber in Washington, Oct. 17, 2013.

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A woman takes a photograph of a mural at the Smithsonian's Air and Space Museum in Washington, Oct. 17, 2013.

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Visitors line up for a tour at the Capitol Visitors Center in Washington, Oct. 17, 2013.

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Visitors to the U.S.S. Constitution, the oldest ship in the United States Navy, walk up the gang plank to the top deck for a tour in Boston, Oct. 17, 2013.

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Visitors at the U.S.S. Constitution, the oldest ship in the United States Navy, step onto the main deck in Boston, Oct. 17, 2013.

Credit: Stephan Savoia/AP

Visitors walk around the Apollo 11 capsule at the Smithsonian's Air and Space Museum after it opened on time, Oct. 17, 2013.

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Tourists walk away after visiting the Lincoln memorial on the morning after a bipartisan bill was passed by the House and the Senate to reopened the government, Oct. 17, 2013.

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Kaity Briscoe shares a laugh with U.S. Park Service Ranger V. Cutright as her husband Jordan Rousseau, center, looks on while waiting for the U.S.S. Constitution, the oldest ship in the United States Navy, to open in Boston, Oct. 17, 2013.

Credit: Stephan Savoia/AP

People pass a Washington Post newspaper box as they head to work near Pennsylvania Ave. in Washington, Oct. 17, 2013.

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A U.S. Park Service truck carries away road closure cones on the morning after a bipartisan bill was passed by the House and the Senate to reopened the government and raise the debt limit in Washington, D.C., Oct. 17, 2013.

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National Park Service employee Paul Fox of Washington, who had been off work for the last 16 days, uses a blower to clean the grounds of the Lincoln Memorial in Washington, Oct. 17, 2013.

Barriers went down at National Park Service sites and thousands of furloughed federal workers began returning to work throughout the country Thursday after 16 days off the job because of the partial government shutdown.

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People exit a Metro station along Pennsylvania Ave., in Washington, Oct. 17, 2013.

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National Park Service regional director Mike Reynolds greets park service employees, including file clerk Lisa Rys-Jones, right, who returned to work after the 16-day federal shutdown, at the entrance to the Lewis and Clark National Historic Trail building in Omaha, Neb., Oct. 17, 2013.

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National Park Service employees remove barricades from the grounds of the Lincoln Memorial in Washington, Oct. 17, 2013.

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National Park Service regional director Mike Reynolds, left, greets a park service employee, who returned to work after the 16-day federal shutdown, at the entrance to the Lewis and Clark National Historic Trail building in Omaha, Neb., Oct. 17, 2013.

Credit: Nati Harnik/AP

The sun begins to rise behind the U.S. Capitol building on the morning after a bipartisan bill was passed by the House and the Senate to reopened the government and raise the debt limit, in Washington, Oct. 17, 2013.

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A worker cleans the fountain at the World War II Memorial in Washington, Oct. 17, 2013.

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People exit a Metro station in Washington, Oct. 17, 2013.

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Passengers fill up Washington Metro subway cars in Arlington, Va., as workers return to their jobs after a budget fight on Capitol Hill that resulted in a partial government shutdown is resolved, Oct. 17, 2013.

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Vice President Joe Biden, left, greets Environmental Protection Agency workers with muffins as they return to work after 16 days of a government shutdown at the William Jefferson Clinton Federal Building in Washington, Oct. 17, 2013.

Credit: Jacquelyn Martin/AP

With the Lincoln Memorial in the distance, a worker cleans the fountain at the World War II Memorial in Washington, Oct. 17, 2013.

Credit: Susan Walsh/AP

A man crosses Pennsylvania Ave., in front of the Justice Department, in Washington, Oct. 17, 2013.

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With the Washington Monument in the distance, Park Service police officers stand on duty at the Lincoln Memorial in Washington, Oct. 17, 2013.